Function maybe_is_nonoverlapping 

pub(crate) const fn maybe_is_nonoverlapping(
    src: *const (),
    dst: *const (),
    size: usize,
    count: usize,
) -> bool

🔬This is a nightly-only experimental API. (ub_checks)

Checks whether the regions of memory starting at src and dst of size count * size do not overlap.

Note that in const-eval this function just returns true and therefore must only be used with assert_unsafe_precondition!, similar to is_aligned_and_not_null.